It is well known that microwaves from radar systems are reflected by iron structures such as a steel tower or an iron bridge and the reflected microwaves have a bad effect on radar systems.
In order to prevent the reflection of the microwaves, there is provided a microwave absorber such as a so-called rubber ferrite. The rubber ferrite is a mixture of ferrite powders and organic high molecular weight compounds.
The inventors have found that microwaves can more effectively be absorbed by using a mixture of ferrite powders and iron powders.
Thus, it has now been found that the reflection of microwave on a surface of iron structures can effectively be prevented by forming coatings comprising ferrite powders and iron powders dispersed in organic high molecular weight compounds such as synthetic resins or rubbers on a surface of iron structures.
The present invention is based on this discovery.